A distribution is approximately Normal when the Normal distribution can be used as an approximate distribution. This is common when the number of samples or parts making up a distribution grows; for example, if you have 100 coin tosses the resulting Binomial distribution is, for most purposes, approximately Normal. This is often helpful as many statistical tests rely on the data being Normally distributed. The Central Limit Theorem explains why it is so common to see approximately Normal distributions.
Also used in hcistats2e: Chap. 4: pages 49, 51
Used in glossary entries: approximate distribution, Binomial distribution, Central Limit Theorem, Normal distribution
